Overview; Sensor; Control Unit; Principle Of Operation - Pentair Goyen Mecair FFA Installation And Operation Manual

3.2 OVERVIEW

The Filter Failure Alarm Monitor (FFA) is suitable for use after bag filters, cartridge filters, cyclones, and a range of other
applications to ensure correct, expected filter performance. The FFA system comprises a sensor and a dedicated control
unit. The sensor is suitable for use in processes of up to 240°C (465°F).
The control unit can be located remotely (maximum distance: 300 m/985 ft).
NOTE: All system components (except the sensor) must be placed in the designated Safe Area (refer to the Functional
Diagram on page 7).

3.2.1 Sensor

The sensor benefits from unique Probe Electrification technology. It comprises a metal probe rod that protrudes into
the stack and connects to the stack via the hexagonal body connected to the sensor enclosure, which contains the
advanced electronics module. The sensor is fitted to the stack using a ½" socket and thread and secured in position
with a lock nut.
Adjustable Alarm Levels
Dual alarming enables operators to configure early warning and limit (high) alarm levels providing flexible sensitivity
to suit the process. The internal setting can be adjusted to avoid triggering false alarms due to temporary spikes,
e.g. during bag-filter cleaning cycles.

3.2.2 Control Unit

The control unit contains the power supply, alarm connections, and has easy-to-use user controls. The control
unit contains the alarm relays, it provides the power for the sensor display and the user controls, allowing the
FFA system to be set up quickly.
The instrument provides a 4–20 mA output scaled to 0–100% of the limit alarm level, thus supporting the integration
of the instrument with external equipment.

3.3 PRINCIPLE OF OPERATION

The FFA sensor utilizes Probe Electrification measurement technology. The sensor measures the interaction between the
particulate in the air stream and the sensing rod to induce a charge signature. It extracts a specific frequency band and
filters out the DC current. The technology outperforms conventional DC tribo-electric systems by extending the range
over which the instrument has minimal cross-sensitivity to changing velocity while remaining unaffected by the build-up
of particulate on the sensing rod, thereby minimizing signal drift and providing reliable results and response.
06 INSTALLATION AND OPERATION MANUAL – OWNER'S RECORD FFA MANUAL – FILTER FAILURE ALARM